WGU D115 Pathophysiology
Mastery Guide 2025/2026 –
Latest Test Questions with
Detailed Rationales (Document
II)
Which of the following valves directs blood flow from the left atrium to the left ventricle?
A. Mitral
B. Tricuspid
C. Aortic
D. Pulmonic - Answer✅A. Mitral
The layer of squamous cells that lines the cardiac chambers and valves is called the:
A. myocardium
B. endocardium
C. epicardium
D. Pericardium - Answer✅B. endocardium
How much does the atrial kick increase the blood volume?
A. 5%-10%
B. 10%-15%
C. 15%-20%
D. 20%-25% - Answer✅C. 15%-20%
Which of the following waves corresponds with the AV valve bulging during ventricular contraction?
A. A wave
B. C wave
, C. D wave
D. V wave - Answer✅B. C wave (The A wave corresponds with atrial contraction, the C wave
corresponds with the AV valve bulging during ventricular contraction, and the V wave corresponds to
atrial filling. There is no D wave.
What portions of the heart does the left anterior descending branch supply?
A. Septal, anterior and apical
B. Lateral and Posterior
C. Lateral and septal
D. Posterior and apical - Answer✅A. Septal, anterior, and apical
What is the name for the arrangement in which separate cells of the myocardium can function
together?
A. Autoregulation
B. Syncytium
C. Ischemia
D. Myocyte - Answer✅B. Syncytium
The structure that is composed of six polypeptide chains, two heavy chains, and four light chains is
called:
A. actin
B. tropomyosin
C. troponin
D. myosin - Answer✅D. myosin
Which electrolyte is necessary for muscle contraction?
A. Na+
B. K+
C. Ca++
D. Mg++ - Answer✅C. Ca++
Which of the following statments is true regarding muscle contraction?
A. Calcium removal from the cytoplasm causes contraction.
B. Calcium entry into the cytoplasm causes relaxation.
C. Cardiac myocytes are terminally differentiated.
D. Contraction of cardiac muscle results from lengthening of sarcomeres. - Answer✅C. Cardiac
myocytes are terminally differentiated.
Which of the following phases of cardiac action potentials is causes by closure of the fast sodium
channels?
A. Phase 0
B. Phase1
C. Phase 2
D. Phase 3 - Answer✅B. Phase 1
Which of the following refers to intermittent, spontaneous generation of action potentials?
A. Rhythmicity
B. Relative refractory
C. Antiarrhythmics
D. Repolarization - Answer✅A. Rhythmicity
Which of the following is not a normal excitation pathway?
A. AV node
B. SA node
C. Bundle of His
D. VA node - Answer✅D. VA node
Mastery Guide 2025/2026 –
Latest Test Questions with
Detailed Rationales (Document
II)
Which of the following valves directs blood flow from the left atrium to the left ventricle?
A. Mitral
B. Tricuspid
C. Aortic
D. Pulmonic - Answer✅A. Mitral
The layer of squamous cells that lines the cardiac chambers and valves is called the:
A. myocardium
B. endocardium
C. epicardium
D. Pericardium - Answer✅B. endocardium
How much does the atrial kick increase the blood volume?
A. 5%-10%
B. 10%-15%
C. 15%-20%
D. 20%-25% - Answer✅C. 15%-20%
Which of the following waves corresponds with the AV valve bulging during ventricular contraction?
A. A wave
B. C wave
, C. D wave
D. V wave - Answer✅B. C wave (The A wave corresponds with atrial contraction, the C wave
corresponds with the AV valve bulging during ventricular contraction, and the V wave corresponds to
atrial filling. There is no D wave.
What portions of the heart does the left anterior descending branch supply?
A. Septal, anterior and apical
B. Lateral and Posterior
C. Lateral and septal
D. Posterior and apical - Answer✅A. Septal, anterior, and apical
What is the name for the arrangement in which separate cells of the myocardium can function
together?
A. Autoregulation
B. Syncytium
C. Ischemia
D. Myocyte - Answer✅B. Syncytium
The structure that is composed of six polypeptide chains, two heavy chains, and four light chains is
called:
A. actin
B. tropomyosin
C. troponin
D. myosin - Answer✅D. myosin
Which electrolyte is necessary for muscle contraction?
A. Na+
B. K+
C. Ca++
D. Mg++ - Answer✅C. Ca++
Which of the following statments is true regarding muscle contraction?
A. Calcium removal from the cytoplasm causes contraction.
B. Calcium entry into the cytoplasm causes relaxation.
C. Cardiac myocytes are terminally differentiated.
D. Contraction of cardiac muscle results from lengthening of sarcomeres. - Answer✅C. Cardiac
myocytes are terminally differentiated.
Which of the following phases of cardiac action potentials is causes by closure of the fast sodium
channels?
A. Phase 0
B. Phase1
C. Phase 2
D. Phase 3 - Answer✅B. Phase 1
Which of the following refers to intermittent, spontaneous generation of action potentials?
A. Rhythmicity
B. Relative refractory
C. Antiarrhythmics
D. Repolarization - Answer✅A. Rhythmicity
Which of the following is not a normal excitation pathway?
A. AV node
B. SA node
C. Bundle of His
D. VA node - Answer✅D. VA node
